1. Field of the Invention
This invention relates to a printer and information processing apparatus.
2. Description of the Related Art
Some information processing apparatus include a free-running counter used as current date and time management means, which will be hereinafter referred to as internal clock. Some of such information processing apparatus can acquire the precise date and time from an external apparatus and adjust the internal clock to the acquired date and time.
Specifically, there are a television and a printer for adjusting the date and time of an internal clock based on the time signal information contained in broadcast waves (for example, refer to patent document 1), an apparatus for accessing an SNTP server and adjusting the time and date of a system clock (a computer, etc., installing a utility program for accessing an SNTP server and adjusting the time and date of a system clock), and the like. A printer having an RTC (real time clock) whose time can be set from a host computer is also available (for example,. refer to patent document 2).
[Patent Document 1]
Unexamined Japanese Patent Publication No. 2000-289296 (p. 3-6, FIG. 1)
[Patent Document 2]
Unexamined Japanese Patent Publication No. 2001-270197 (p. 7-8, FIG. 3)
The already existing information processing apparatus that can acquire the precise date and time from an external apparatus and adjust the internal clock to the acquired date and time as described above is an apparatus for adjusting the date and time when the user gives a command or in the cycle previously specified by the user.
Even information processing apparatus of the same model differ in precision of internal clock (how much the clock loses or gains) . Thus, if the date and time of the clock are adjusted with a frequency more than necessary, the essential processing of the information apparatus may be adversely affected (completion of the essential processing may be a little delayed). If the information processing apparatus inquires of an SNTP server about the date and time, the SNTP server and the network resources are also used wastefully.
Thus, in the existing information processing apparatus, the following intricate work procedure for specifying (setting) the time interval is performed: First, standard time interval is set as the time interval for adjusting the date and time and after how much the internal clock loses or gains is observed, if the loss or gain is beyond the allowable range, the time interval for adjusting the date and time is again set to a shorter time interval.